What Is Vulcanization?

Vulcanization is a treatment process for natural rubber that makes it much more durable and suitable for a wider range of applications than would be otherwise possible. Credit for the discovery of this process goes to inventor Charles Goodyear, who developed it in the 1830s, although a different inventor took out a patent in the 1840s. Vulcanization revolutionized the rubber industry and made a number of industrial products, from reliable car tires to balls for games, possible. Today a number of different techniques are used in the vulcanizing process.

Natural rubber tends to be extremely sticky. In warm temperatures, it deforms, while in cold temperatures, it turns very brittle. These characteristics make it largely useless for many applications. When rubber was introduced to people in the West from the regions of South America where it originates, it was primarily considered a curiosity, without any obvious applications. This changed when Goodyear developed a technique for processing the highly elastic material.

In the vulcanization process, the rubber is treated with sulfur or other chemicals. This creates new polymer bonds and an extremely durable material. In the heat, it retains its shape, and in cold weather, it remains flexible. It is also less sticky after processing, eliminating problems like smearing and gumming up components. Manufacturers were also able to create extremely hard, strong rubbers for heavy duty applications like aircraft tires.

Companies with an interest in rubber production often have vulcanization projects ongoing in their research and development departments. They look for new ways to process rubber in order to cut costs and expand their product offerings. When these techniques are successful, they can allow a company to patent proprietary processes to make secondary income by licensing the rights. Although basic vulcanization technology is in the public domain, specialized processes can offer more control and more options for manufacturers.

Firms can handle rubber in a variety of ways as they process it to develop different traits. Some rubbers need to be harder or more flexible than others, and in some cases very high tolerances are necessary. Others may need to operate only in a limited range of temperatures, and thus do not need such extensive treatment before they are ready for use. Different vulcanization techniques can allow companies to choose from a library of options when they prepare rubber products, both for new products and the replacement of worn rubber components in existing products.